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arXiv · 2510.08821

Wild Stacky Curves and Rings of Mod p Modular Forms

Andrew Kobin·David Zureick-Brown
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Abstract

We extend work of Voight and the second author to compute the log canonical ring of a wild stacky curve over a field of characteristic $p > 0$, which allows us to compute rings of mod $p$ modular forms of level $\Gamma_{0}(N)$. Our approach also reveals that in characteristics $2$ and $3$, there are infinitely many levels $N$ for which there are weight $2$ modular forms of level $\Gamma_{0}(N)$ that do not lift to characteristic $0$.

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Andrew Kobin, David Zureick-Brown. 2025-10-09. Wild Stacky Curves and Rings of Mod p Modular Forms. https://arxiv.org/abs/2510.08821

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